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饵料和水质条件是影响养殖生产的重要因素。本研究探讨不同类型的营养剂对水体中浮游生物生长及水体理化性质的影响。实验通过对水体施用无机营养剂(inorganic nutrients,IN)、微量营养添加剂(micronutrients additives,MA)及复合营养剂(complex nutritional preparation,CNP)和空白对照(no fortification,NF)处理,测定水体中溶解氧(dissolved oxygen,DO)、氨氮(ammonia,NH_3-N)、亚硝酸氮(nitrite,NO_2-N)、总氮(total nitrogen,TN)及总磷(total phosphorus,TP)的变化,并采用变性梯度凝胶电泳(polymerase chain reaction-denaturing gradient gel electrophoresis,PCR-DGGE)技术研究水体浮游生物的群落结构。理化指标的结果表明,IN极显著提高水体DO、NH_3-N、NO_2-N和TN的含量(P<0.01),而MA仅对NH_3-N具有极显著的提高作用(P<0.01),并极显著降低NO_2-N水平(P<0.01),其他理化指标均与NF无显著差异。原核生物DGGE图谱可知,NF组的条带数最多,检测到44条,其次为IN组(37条)和MA组(36条),而CNP组最少,仅34条。多样性指数(shannon-wiener diversity index,H’)和均匀度指数(pielou evenness index,J)以NF组最高,分别为3.78和0.91,CNP组最低,分别为3.53和0.85。真核生物DGGE图谱显示,CNP组条带数最多,检测到25条,NF组(22条)和MA组(21)条次之,而IN组最少,仅18条。CNP组多样性指数和均匀度指数均最大,为3.22和0.86,而IN组最小,为2.89和0.77。由此可见,添加营养剂后水体中TN和TP均明显提高,IN组中的有害物质和有害菌大量增加,而MA则降低了水体中有害物质和有害菌的含量,CNP组中浮游生物多样性最高,能够为水体提供充足的营养物质,同时对水体环境具有较好的改善作用。实验结果为健康养殖及改善水体生态环境提供理论依据。
Feed and water quality conditions are important factors affecting aquaculture production. This study investigated the effects of different types of nutrients on the growth of plankton and the physicochemical properties of water bodies. The experiment was carried out on the water body by applying inorganic nutrients (IN), micronutrients additives (MA) and complex nutritional preparations (CNP) and no fortification (NF) The changes of dissolved oxygen (DO), ammonia (NH_3-N), nitrite (NO_2-N), total nitrogen (TN) and total phosphorus (TP) The community structure of plankton in water was studied by PCR-DGGE (polymerase chain reaction-denaturing gradient gel electrophoresis). The results of physico-chemical indicators showed that IN significantly increased the contents of DO, NH_3-N, NO_2-N and TN in water (P <0.01), while MA only significantly increased NH_3-N (P <0.01) Significantly reduce NO 2-N levels (P <0.01), other physical and chemical indicators were no significant difference with NF. The prokaryotic DGGE patterns showed that the number of bands in NF group was the highest, 44 bands were detected, followed by IN group (37) and MA group (36), while the CNP group was the least, only 34 bands. The index of diversity (Hn) and pielou evenness index (J) were the highest in NF group (3.78 and 0.91, respectively) and the lowest in CNP group (3.53 and 0.85 respectively). The eukaryotic DGGE pattern showed that the number of bands was the highest in CNP group, 25 bands were detected, while NF group (22) and MA group (21) were the second, while IN group was the least, only 18 bands. CNP group diversity index and evenness index were the largest, 3.22 and 0.86, while IN group minimum, 2.89 and 0.77. Thus, TN and TP in water were significantly increased after addition of nutrients, a significant increase in harmful substances and harmful bacteria in IN group, while MA reduced the content of harmful substances and harmful bacteria in water, the diversity of plankton in CNP group The highest sex, able to provide adequate water nutrients, while the water environment has a better improvement. The experimental results provide a theoretical basis for healthy farming and improving the ecological environment of water bodies.